Hymnorq 10-Piece 1/4 Inches Cobalt Drill Bit Set – M35 Grade (5% Cobalt) Steel, Fully Ground, Dual Twist Flute, 135 Degree Split Point, Jobber Length, Bronze Finish, with Tough PP Storage Case
Product Description
Hymnorq 10-Piece 1/4 Inches Cobalt Drill Bit Set – M35 Grade (5% Cobalt) Steel, Fully Ground, Dual Twist Flute, 135 Degree Split Point, Jobber Length, Bronze Finish, with Tough PP Storage Case
- Industrial-Grade M35 Cobalt Steel: Made with 5% cobalt-enriched M35 steel, these 1/4" drill bits deliver superior strength, heat resistance, and wear durability—ideal for drilling stainless steel, cast iron, and other tough metals.
- Dual Twist Flute & Fully Ground Design: Features a fully ground, dual twist flute for smoother drilling, faster chip removal, and greater precision—reducing friction and extending tool life during heavy-duty use.
- 135° Split Point for Precision Starts: The 135° split point tip ensures accurate starts with minimal walking, making it easier to drill clean, precise holes on hard or curved surfaces..
- Straight Shank with Chamfered End: Designed with a straight shank for a secure fit in standard drill chucks and a chamfered end for smooth bit changes and better grip stability during operation.
- Durable Transparent PP Case: Comes in a tough, transparent plastic case that keeps all 10 drill bits organized, protected, and easily visible—perfect for professionals and DIYers who value efficiency and tool care.
OVERVIEW
Different types of drill bits are used to cut holes in different types of materials. This set of M35 cobalt steel drill bits are particularly successful in cutting through hard metals such as stainless steel and cast iron, although they can be used for softer materials, too.
Cobalt drill bits are not made of pure cobalt, but rather a steel alloy with certain percent cobalt. The 5-percent alloy is known as M35 grade. The cobalt increases the strength of the steel and makes it more heat-resistant; this is an important factor in drilling hard materials because the friction of metal against metal can produce high temperatures that damage the material or the drill bit.
Tests shows that the M35 cobalt steel drill bits can penetrate a 5mm-thick 304 stainless steel plate in 5 seconds.
Cobalt drill bits are more expensive than other drill bits, but if you regularly drill through metal, they are a good investment since they tend to last longer. With an extended tool life, Hymnorq cobalt drill bits will give you the lowest cost per hole drilled.
NOTICE: Please use with cooling liquid to prolong the working life of the drill bits and to avoid overheating and breakage.
This set M35 grade cobalt drill bits are not suitable for hardened steel / high carbon steel.
TECHNICAL DETAILS:
Material: M35 Cobalt Steel
Angle Point: 135 Degree
Flute Type: Spiral
Hardness: Rockwell 67
Shank Type: Straight Shank
WHAT'S INCLUDED:
1/4" Cobalt Steel Drill Bit x 10pcs
Plastic Case x 1pc
BUY WITH CONFIDENCE:
If you're not completely satisfied with the product quality, please contact us. Refund or free replacement.
Technical Specifications
You might also like
1/8-Inch Cobalt Steel M35 Jobber Length Twist Drill Bits for Hard Metal, Stainless Steel, Pack of 12
3/16-Inch Cobalt Steel M35 Jobber Length Twist Drill Bits for Hard Metal, Stainless Steel, Pack of 12
IRWIN Tools 63124 3/8-Inch Cobalt 135-Degree Jobber Length Drill Bit, Pack of 6
Pack of 12, 3/16-Inch Titanium Nitride Coated Drill Bit, High Speed Steel, Jobber Length, for Metal, Plastic, Wood
IRWIN Tools 63112ZR 3/16-Inch Cobalt 135-Degree Jobber Length Drill Bit, Pack of 12
12 PCS,1/4", HSS Black and Gold Coated Twist Drill Bits, Metal drill, ideal for drilling on mild steel, copper, Aluminum, Zinc alloy etc. Pack in Plastic Bag